Plate for circuit breakers



July 25, 1933. T. LINDSTROM 1,919,438

PLATE FOR CIRCUIT BREAKERS Filed Aug. 20, 1929 Fig.1.

'IIIIIIIIl-\\\\\\\ INVENTOR Tare Linaszr'om Patented July 25, 1933 UNITED STATES,

PATENT OFFICE TUBE LINDSTROM, F WILKINSBURG, PENNSYLVANIA, ASSIGNOR TO WESTTNGHOUSE ELECTRIC 8c MANUFACTURING COMPANY, A CORPORATION OF PENNSYLVANIA PLATE ron cmcurr BREAKERS Application filed August 20, 1929. Serial No. 387,159.

My invention relates to circuit interrupters and particularly to arc-extinguishing means therefor.

One object of my invention is to form an arc-extinguishing device for a circuit interrupter that shall comprise a plurality of deionizing plates, portions of which are made of magnetic material.

Magnetic materials have been employed heretofore in extinguishing devices that are positioned adjacent to arc paths for attracting the arc thereon where it is deionized and extinguished. Such a device is to be found in the copending application Jennings, Serial No. 606,565, filed December.l3, 1922, and assigned to the assignee of the present invention. While this type of arc-extinguishing device has proved satisfactory when employed on circuit interrupters of small interrupting capacities, on circuit interrupters of large capacities, the plates increase to such proportions that the extinguishing devices become large and cumbersome.

In practicing my invention, I take advantage of the additional surface provided by the association of non-magnetic plates with those of magnetic'material when the former are positioned between the arc path and the magnetic plates. In such construction, the entire surface of the non-magnetic plates is available forthe movement of the arc thereacross when the arc is attracted to ;constructed entirely of magnetic material, only one-half of the surfacethereof is avail- ,"able "for are travel, 7 as the arc becomes 1 stable at the center of the plates because the field thereabout will in equilibrium. It is, accordingly, anotherobject ofmy i 'the magnetic plates; .When the plates are v invention to provide plates for an arc-ex-- .tinguishing device of r the. above-mentioned jtypemthat shall embody portions of magneticw'andwznon-magnetic materials assonciated in such jmanner that the :portions of magnetic material, are: ;more;. remote from the arcqpath.

a t Myinventionlwill be; better understood by referring to the following description,

of Oliver S.

taken in conjunction with the accompanying drawing wherein:

Fig. 1 is a plan View of a contact memher and an arc-extinguishing device embodying my invention;

Fig. 2 is a side View, in section, of the extinguishing device of Fig. 1, taken along the line 1III of that figure;

Fig. 3 is a plan view of an element of my arc-extinguishing structure shown in Fig. 1; and

Fig. 1 is a side View of the arc-extinguishing element shown in Fig. 3.

My invention comprises, in general, a

base 1 upon which .a contact member 2 and an arc-extinguishing device 3 is mounted in fixed positionrrelative to each other. A movable contact member 1 cooperates with the stationary contact member. 2 and the arc-extinguishing device 3 and is actuated to engage and be disengaged from the contact member 2 by an operating mechanism that is not shown in the drawing as it constitutes no part of the' present invention. Any operating device known in the art to be suitable may be employed.

The contact member 2 is provided with a contact stud 5 that extends through the base 1 and is the means for clamping the contact member 2 thereon through the medium of the nut 6. A shunt and stud (not shown) are attached to the movable contact member 4. and the base 1, respectively, and are the means of completing a circuit through the contact members 2 and 4 and the stud 5.

The deionizing device 3 comprises a series of plates 7 that are mounted on the base 1 by-insulated bolts 8 and are spaced apart thereon 'apred'etermined distance by the washersl),

-Referring to Figs. 3 and 4, the plates, 7 comprise a U-shaped portion llthat is made of magnetic material and a portion 12 that is intimately. associated therewith. The plate12 may be made of any material that is non-magnetic and is preferably constructed from a conducting material, such as copper. It is to. be understood, however,

that'non-conducting materials'may be emoxidizing characteristic when placed adjacent to the arc path to assist in the deionization of the arc.

Any material other than that which is magnetic will be suitable to provide additional deionizing area over which the arc will be made to travel by the attracting properties of the surrounding magnetic plates. While the structure herein shown has a plate located only on one side of. the path of the are, it is to be understood that different forms and shapes of plates may be employed; for example, the plates may be made in the shape of washers, one within the other, so that the arc is entirely surrounded by the plates of non-magnetic and of magnetic material.

Any means may be employed to retain the plates in unit relation with each other, the method of peening the two surfaces together, as shown by tool marks 13, has proved satisfactory. However, it is not necessary to have both plates associated in the same plane. Such a relation is shown herein as a preferred embodiment because of the edonomy in space when mounting such plates. It is to be understood that the plates may be lapped or otherwise positioned so long as the plates bear a lateral relation to 30 each other with respect to the arc path, as

7 above set forth.

It will thus be seen that I have provided plates for the deionizing device of a circuit interrupter that embodies the roperties of attracting the arc to the'surfaces thereof and having intimately associated therewith additional plates lacking the said attracting properties and positioned between the attracting plates and the arc path to ensure sufiicient deionizing surface for the. are without materially increasing the size of the plates.

While I have illustrated but one embodiment of my invention, it will be apparent to modifications, substitutions, additions and omissions may be made in the apparatus illustrated without departing from the spirit and scope of my invention, as set forth in the appended claims.

I claim as my invention:

1. In an arc extinguishing device, a plurality of sheets of non-magnetic conducting material having open spaces therebetween, 5 and a plurality of sheets of magnetic material each having an end portion and a pair of leg portions, said sheets of magnetic material having open spaces therebetween and being positioned in planes substantially parallel to said sheets of non-magnetic material with said leg portions extending along the sides of said sheets of non-magnetic material for moving the arc thereinto.

2. In an arc extinguishing device, a pluralitv of sheets of non-magnetic conducting ducting plates and splitting it up material having open spaces therebetween, and a plurality of sheets of magnetic mate- "rial each having an end portion and a pair of leg portions extending along opposite sides of said sheets of non-magnetic conducting material and magnetic means projecting beyond one edge of each of said sheets of non-magnetic conducting material for moving the arc against said edges for splitting up the are into a plurality of short arcs.

3. In a circuit interrupter, means for establishing an arc, means for extinguishing the are positioned along the arc path, a plurality of plates of magnetic material positioned at spaced intervals along substantially the whole length of the arc path in planes transverse thereto, said plates of magnetic material having a portion of U-sha e surrounding said extinguishing means r distorting the magnetic field due to the arc current to move the are into said extinguishing means and open spaces continuous through both said extinguishing means and said magnetic plates.

4. In a circuit interrupter, means for establishing an arc, means for extinguishing the are positioned along the arc path comprising a plurality of plates of non-magnetic conducting material having open spaces therebetween positioned in planes transverse to the arc path alon substantially its whole length, a plurality 0 plates of magnetic material positioned along substantially the whole length of the arc path, each of said 10 magnetic plates having an end portion and a pair of leg portions and being positioned co-p'lanar with one of said non-magnetic conducting plates with its leg portions extending along opposite sides thereof for 1 moving the are into said non-magnetic coninto a plurality of short arcs, and open spaces between said magnetic plates continuous with the open spaces between said non-magnetic con- 11o ducting plates to permit expansion of the arc gases transversely to the arc path between both of said sets of plates.

5. In an arc extinguishing structure, a

* plurality of plates of non-magnetic conducting material having open spaces therebetween, means for moving the arc intosaid non-magnetic conducting plates and splitting it up into short arcs movable on said non-magnetic conductin plates, said means 1 including a plurality of plates of magnetic material, and each of said plates of nonmagnetic conducting material having an edge portion conductively engaging one of said plates of magnetic material and being 12 insulated from the other of said plates both of magnetic conducting material and of nonmagnetic conducting material.

6. In an arc extinguishing structure, a plurality of plates of non-magnetic conduct- -in g material having open spaces therebetween, means for moving the are into sald non-magnetic conducting plates and splitting it up into short arcs movable on said non-magneticconducting plates, said means including a plurality of plates oi? magnetic conducting material each having an end portion and a pair of spaced projecting leg portions having an air gap between their outer ends, and each of said plates of non magnetic conducting material being positioned across the space between said poi tions conductivelg/ engaging one of s id plates of magnetic conducting and losing insulated from the other of said both of magnetic conducting material and of non-magnetic conducting material.

7. In an arc extinguishing structure, a plurality of plates of non-magnetic conducting material having open spaces therebetween, means for moving the are into said non-magnetic conducting plates and split Gib O etic ceiiduc ni- L'setween portions of 3 of magnetic conducting material said spaces connecting with said open b tween the plates of non-magnetic co ing material forming continuous ve passages through both of said types c. plates;

TUBE 

